Retrofitting of reinforced concrete columns with honeycombed cover

Abstract

In this research, a significant attention has been given to the experimental investigation of retrofitting and rehabilitation of honeycombed reinforced concrete (RC) columns. Ten RC columns specimens were tested and discussed in the experimental tests; five of them are for the square section with a dimension of cross section (200 X 200) mm, and five for the circular section with a cross section diameter of (200) mm. The total length for both sections is (1200) mm. The honeycombed zone in the base and middle of specimens was considered as a percentage of the total columns. The honeycombed columns were repaired with cement-based materials prior to the test. All columns were tested axially until failure. For each tested RC columns, the ultimate load, cracking load, mode of failure, and load versus lateral and axial displacement were recorded. Test results showed the strength and load capacity of the treated column exceed the one for the control column with different percentages based on the cross-section of RC column, and location and size of the honeycomb defect. The increase in ultimate load ranges from 3% to 16% for square section, while for circular section the range of increase starts from 3% to 17%. It is worth noting that this percentage of increase is higher as the size of the honeycomb increases and vice versa.